Opinion: A primer on cannabis oil cartridges

Thursday

The popularity of cannabis oil vaporizer cartridges, otherwise known as “tanks” among cannabis users, is exploding at a rate faster than any other product on dispensary shelves.

According to data submitted by Colorado’s recreational cannabis industry, cannabis vaporizer cartridge sales increased by 400 percent in 2016 alone. If you’ve been a medical cannabis patient here in Massachusetts prior to the first recreational shops opening Nov. 20, you’ve witnessed shortages in this hot commodity.

Cannabis vaporizer cartridges are small tanks, typically made of glass or plastic, and pre-filled with a cannabis concentrate. Similar to traditional e-cigarettes, the cannabis cartridge screws into a rechargeable battery containing a button which atomizes, or activates, the vapor almost immediately once pressed.

There are obvious reasons why cannabis oil cartridges are so popular. They’re convenient, easily concealed, smokeless and virtually odorless, and most of all, pack a punch with a THC content typically at least three times that of cannabis flower. The absence of odor makes them popular for concerts, bars and according to some, work.

When the first medical dispensaries opened in Massachusetts back in 2015, only one tier of pen cartridge existed for sale. They were plastic tanks filled with murky colored butane-extracted cannabis concentrate. Now, if you enter a dispensary, or, as of Nov. 20, a recreational cannabis shop, you are most likely going to find three different types of cartridges, each filled with cannabis oil extracted via one of several methods -- all with a different price tag.

The three most-common cannabis extracts you will find in cartridge form are those derived from distillation, CO2 extraction or live resin extraction. They will often be split up this way on the product menu. But it’s still unclear to many novices what these things mean, so here’s a brief breakdown of each.

Distillation

Distillate is clear, highly refined oil which can be made from any cannabis extract, regardless of quality. The heat strips away most of the cannabinoids and the terpenes, often leaving only THC and CBD behind.

Terpenes are a very important part of cannabis -- and will be the topic of a full column another time -- but for right now, we’ll just look at terpenes as the taste and the genetic blueprint of a specific cannabis strain. The problem I have with distillate is its need for additives to make the viscosity compatible with the heat output of the battery.

Natural terpenes contribute to keeping the oil's viscosity at a level which can be vaporized by a pen. Once these are stripped away, you have a thick, yellowy-clear oil with a THC percentage of around 90 percent, making it almost solely recreational with minimal medical benefits.

Terpenes are often added in after to give the impression of a specific strain and to serve as an additive to loosen up the oil. If you are purchasing a distillate cartridge, just make sure the added terpenes are listed as cannabis-derived, not botanically derived.

Distillate is the least-expensive cartridge, typically priced at $35 to $45.

CO2 extraction

The most-popular cannabis vaporizer cartridges by far, are those made with oil collected from CO2 extraction. CO2 extracts are the most compatible with vaporizer cartridges because they do not require additives of any kind to meet the viscosity needed to function in the battery atomizers made for them.

The lack of harsh solvents and intense heat allows the CO2 oil to maintain its cannabis-derived terpenes, which actually serve as both a natural thinning agent and retains a strain’s specific flavor.

CO2 vaporizer cartridges will typically run you around $75, although because of recreational cannabis’ launch, I’ve seen the same cartridges shoot up to $100 each.

Live resin extraction

And finally, my personal favorite extract to use in pen cartridges -- live resin. These are less common, as they involve a more time-consuming process and contain less THC, making those seeking a recreational high less apt to purchase them.

Live resin retains a high terpene percentage, giving it a uniquely pungent flavor while preserving the plant’s cannabinoids, as terpenes also serve as a plant’s genetic blueprint. Extracting live resin involves flash-freezing a plant immediately after harvest using dry ice and keeping it at freezing temperatures throughout the extraction process.

This method, also called “cold press,” retains the plant’s valuable terpene profile, which in turn preserves many of the valuable cannabinoids lost in all other extraction methods. Live resin is the only extract which I consider to be medically beneficial. Although a bit harder to find than CO2 cartridges, they are about the same price.

Extracts like the ones described above aren’t for the beginner. If you are new to cannabis and prefer vaporizer cartridges rather than flower, I suggest live resin for its less-intense high and similarity to flower.

Beware of the many brands of black-market cartridges now readily available. These are often butane extracted oil combined with cheap, dangerous additives for thinning out the mixture. The most common additive to black-market cartridges is propylene glycol, which can turn into carcinogenic compounds when exposed to high heat.

So be careful with your newly acquired freedom to purchase cannabis extracts legally. Know what you’re ingesting, and never be afraid to ask questions.

Gregg Padula is an employee of GateHouse Media New England. He has experience in several areas of the cannabis industry, and now serves as an advocate for both patients' and workers’ rights. He can be reached at gpadula@wickedlocal.com.